title: Changes in tibial bone density measured from standard radiographs in cemented and uncemented total knee replacements after ten years' follow-up.
abstract: Stress shielding resulting in diminished bone density following total knee replacement (TKR) may increase the risk of migration and loosening of the prosthesis. This retrospective study was designed to quantify the effects of the method of fixation on peri-prosthetic tibial bone density beneath cemented and uncemented tibial components of similar design and with similar long-term survival rates. Standard radiographs taken between two months and 15 years post-operatively were digitised from a matched group of TKRs using cemented (n = 67) and uncemented (n = 67) AGC tibial prostheses. Digital radiograph densitometry was used to quantify changes in bone density over time. Age, length of follow-up, gender, body mass index and alignment each significantly influenced the long-term pattern of peri-prosthetic bone density. Similar long-term changes in density irrespective of the method of fixation correlated well with the high rate of survival of this TKR at 20 years, and suggest that cemented and uncemented fixation are both equally viable.
authors.affiliation: Joint Replacement Surgeons of Indiana Research Foundation, 1199 Hadley Road, Mooresville, Indiana 46158, USA.
authors.forename: S R
authors.initials: SR
authors.lastname: Small
authors.forename: M A
authors.initials: MA
authors.lastname: Ritter
authors.forename: J G
authors.initials: JG
authors.lastname: Merchun
authors.forename: K E
authors.initials: KE
authors.lastname: Davis
authors.forename: R D
authors.initials: RD
authors.lastname: Rogge
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000379:methods*; D001843:Bone Cements / Q000009:adverse effects*; D015519:Bone Density; D002484:Cementation / Q000009:adverse effects / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design / Q000009:adverse effects*; D011475:Prosthesis Failure; D011859:Radiography; D012189:Retrospective Studies; D015996:Survival Rate; D013977:Tibia / Q000000981:diagnostic imaging*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D001843:Bone Cements
keywords: BMD; Bone density; Cement; Radiographs; Stress shielding; Tibia